Very high speed commercial digital presses print variable data at rates of up to thousands of pages per minute. Such commercial digital presses commonly print on a print media supplied as rolls of print media. A continuous web of the print media is fed through the digital press and is printed on one or both sides of the print media using one or more printheads. The web of print media can then be fed to finishing equipment that converts the print media from a continuous web format to the desired final form needed for the consumer. Finishing equipment can include, but is not limited to, slitters, cutters, perforators, post-coating equipment, and folders.
Each print job can include different setup conditions for the various finishing equipment. To facilitate such print job specific setups, automatic finishing equipment has been developed which is able to receive setup instructions from a printer controller to define finishing action on the print media. For instance, automatic slitters may have a number of slitter blades which are movable to the desired slit positions in response to printer instructions. While such automatic finishing equipment facilitates setup changes from job to job, the changes do not happen instantaneously. Adjustment times, including time to calibrate or verify the setup conditions can range from 30 seconds to a few minutes.
Such changes are more likely to occur at transitions between print jobs. It is envisioned that the metadata channel may be an appropriate means to send these set up commands to the finishing or preprinting equipment. The finishing equipment, however, will need time to respond to the instructions before the change is implemented. During the transition scrap is generated.
To minimize scrap, the printer controller may slow down the printing press prior to initiating the change in setup conditions. Then during the time that the setup change is occurring, a reduced volume of scrap will be generated. Once the finishing equipment is ready for the new job, the printer will begin sending data to the printheads for the new job.
The slowing down of the press will have reduced scrap, however, if printing is delayed until a response is received that the finishing equipment that ready, all the paper in the paper path between the first printhead and the finishing equipment will be scrap.